Stabilized organic material



States 3,146,273 STABILIZED GRGANIC MAT EL Harold D. Orlofif, Oak Park,and John P. Napolitano, Royal (lair, Mh-, assignors to EthylCorporation, New

York, N.Y., a corporation of Virginia BQ Drawing. Filed July 28, 1960,Ser. No. 45,784 2 Claims. (1. 260--619) This invention relates to novelphenolic compounds containing a halogen substituent on the benzene ring,and more particularly to the use as antioxidants of methylenebis phenolswhich are halogen substituted.

It is an object of this invention to provide novel phenolic compoundshaving an extremely high degree of antioxidant and stabilizing activityin a wide variety of organic compositions. Another object of thisinvention is the provision of phenolic compounds which are outstandingantioxidants in organic media such as fuels, lubricants and polymericmaterial. A still further object is the provision of stabilized organicmaterial containing a novel phenolic compound. Another object is toprovide novel methods for the preparation of phenolic compounds. Otherobjects will become apparent by the following specification.

The objects of this invention are in part accomplished by a compoundhaving the formula:

' on OH a)a t ala H where X is a halogen selected from the classconsisting of chlorine, bromine and iodine.

The most particularly perferred compound of this invention is2,2'-methylenebis-(4-chloro-6-tert-butylphenol) which is both readilyprepared and, as will be further illustrated below, is an outstandingantioxidant additive.

The compounds of this invention find important utility as antioxidantsin a wide variety of oxygen sensitive materials. Thus, an embodiment ofthis invention is organic material normally tending to undergo oxidativedeterioration in the presence of air, oxygen, or ozone, protectedagainst such deterioration by the inclusion therein of a smallantioxidant quantity, up to about 5 percent, of a2,2-methylenebis-(4-halo-6-tert-butylphenol) as defined above. As notedabove, a particularly preferred embodiment of this invention is organicmaterial containing the compound 2,2 methylenebis(4-chloro-6-tert-butylphenol).

Thus, liquid and solid products derived from petroleum crude are foundto possess greatly increased storage stability by the use of anantioxidant of this invention. For example, gasoline jet fuel, kerosene,fuel oil, turbine oils, insulating oils, motor oils and various waxeshave increased oxidative stability when they contain an antioxidant ofthis invention. Likewise, liquid hydrocarbon fuels which containorganometallic additives such as tetra ethyllead and otherOrganometallic compositions which are used as fuel additives attainappreciably increased oxidative stability by the practice of thisinvention. Furthermore, such fuels which contain halogen andphosphorus-containing scavengers for these Organometallic compounds arebenefited by the practice of this invention. In addition to increasedstorage stability, lubricating oils and functional fluids, such asautomatic transmission and hydraulic fluids, both those derived fromnaturally occurring hydrocarbons and those synthetically prepared,achieve a high degree of resistance to oxidation during use at elevatedtemperatures by the practice of this invention. It has been found thatlubricating oils may be employed at extremely high temperatures withoutundergoing oxidative degradation when protected by an antioxidant ofthis invention. The addition of small quantities of the compositions ofthis invention to such materials as hydraulic, transformer and otherhighly refined industrial oils, as well as crankcase lubricating oilsand lubricating greases prepared from these oils by the addition ofmetallic soaps, greatly increase their resistance to deterioration inthe presence of air, oxygen or ozone. Furthermore, the organic soapsused in the preparation of lubricating greases are themselvesstabilized'by the practice of this invention.

Organometallic compositions such as tetraethyllead and tetraethylleadantiknock fluids containing halohydrocarbon scavengers, dyes and whichmay contain various phosphorus compounds and other Organometallicadditives are stabilized against deterioration during storage by theaddition thereto of an antioxidant quantity of the compositions of thisinvention.

The compositions of this invention are also extremely effectiveantioxidants for elastomers including high molecular weight unsaturatedhydrocarbon polymersincluding both those derived from naturallyoccurring sources and those synthetically prepared. Thus, naturalrubbers and synthetic rubbers, including oil extended rubbers and sulfurvulcanized rubbers are greatly benefited by the practice of thisinvention. Examples of the synthetic rubbers protected by the practiceof this invention include such synthetics as polybutadiene,methylrubber, polybutadiene rubber, butyl rubber, SB-R rubber, GR-Nrubber, piperylene rubber and dimethylbutadiene rubber.

The practice of this invention is also useful in protecting paraflin andmicro-crystalline petroleum waxes against the oxidative deteriorationwhich leads to rancidity.

The compositions of this invention are also outstand-.

ing antioxidants for various organic compounds and polymeric materialsincluding polystyrene, polyvinylchloride, polyvinyl acetate, variousexpoxide resins, polyester resins and polymers, including alkyds, andpolymers of monoolefins, such as polyethylene and polypropylene.

A preferred embodiment of this invention is rubber (including naturalrubber, sulfur vulcanized rubber and synthetic rubber) normallysusceptible to oxidative deterioration inhibited against suchdeterioration bya small antioxidant quantity, up to about 5 percent of a2,2- methylenebis-(4-halo-6-alkylphenol) compound as .defined above.

Although concentrations of the 2,2'-methylenebis-(4- halo-6-alkylphenol)compounds of this invention, up to 5 percent, may be employed, thecompounds are such effective stabilizers that concentration ranges offrom 0.001 to about 2 percent by weight are usually sufficient toeffectively stabilize the material to be protected (based on the weightof the material). The most preferred concentration range is from about0.2 to about 1.5 percent by weight of the additive based on the weightof material to be protected. Deviations from these concentrations.

are acceptable and sometimes useful dependingupon the initial degreeof'instability of the material being stabilized and the severity ofconditions to which the finished product is to be subjected. Smalleramounts ofthe compounds may be employed when the material is to be usedat lower temperature and oxidation in storage is the primary problem. i

The synthetic lubricants which are enhanced bythe practice of thisinvention are, in general, non-hydrocarbon organic compositions; ile.,organic compositions which contain elements other than carbon andhydrogen. Ex

amples of general classes of material which are protected agamstoxidative deterioration by the inclusiontherein of a2,2'-methylenebis-(4-halo-6-tert-butylphenol) of this invention includediester lubricants, silicones, halogen containing organic compoundsincluding the fluorocarbons; polyalkylene glycol lubricants, and organicphosphates which are suitable as hydraulic fluids and lubricants.Excellent results are obtained when a2,2-methylenebis-(4-halo-6-tert-butylphenol) is added to any member ofthese classes of materials; however, it has been found that exceptionaloxidative stability is imparted to diester lubricants by the practice ofthis invention. Thus a synthetic diester lubricant containing from about0.001 to about 2 percent by weight of 2,2'-methylenebis-(4-halo-6-tert-butylphenol) constitutes a preferred embodiment of thisinvention. The synthetic diester oils stabilized by the practice of thisinvention include sebacates, adipates, etc., which find particular useas aircraft instrument oils, hydraulic and damping fluids, and precisionbearing lubricants. These diester oils are exceedingly difficult tostabilize under high temperature conditions. In this invention, use canbe made of a wide variety of diester oils of the type described inIndustrial and Engineering Chemistry, 39, 484-91 (1947). Thus, use canbe made of the diesters formed by the esterification of straight chaindibasic acids containing from 4 to about 16 carbon atoms with saturatedaliphatic monohydric alcohols containing from 1 to about 10 carbonatoms. Of these diester oils, it is preferable that the alcohol used intheir preparation be a branched chain alcohol because the resultantdiesters have very valuable lubricating properties and the inhibitor ofthis invention very effectively stabilizes these materials againstoxidative deterioration. Thus, use can be made of oxalates, malonates,succinates, glutarates, adipates, pimelates, suberates, azelates,sebacates, etc.

The diester lubricants used in the lubricant compositions of thisinvention have the formula:

COORI COORz where R is an aliphatic hydrocarbon radical which may besaturated or unsaturated and has from 2 to 14 carbon atoms and R and Rare straight or branched chain alkyl groups. The diesters utilized inthe preferred lubricant compositions include esters of succinic,glutaric, adipic, pimelic, suberic, azelaic and sebacic acid. Typicalexamples of such esters are diisooctyl azelate, di-(2-ethylhexyl)sebacate, di-sec-amyl sebacate, diisooctyl adipate, di-(Z-ethylhexyl)adipate, di-(Z-ethylhexyl) azelate, di- (1-methyl-4-ethyloctyl)glutarate, diisoamyl adipate, di- (Z-ethylhexyl) glutarate,di-(Z-ethylbutyl) adipate, ditetradecyl sebacate and di-(2-ethylhexyl)pinate.

The preferred diesters are generally prepared by esterifying one mole ofa dicarboxylic acid having the general formula: HOOC-(CH COOH, where xis an integer of from 2 to 8, with 2 moles of a branched chain alcoholcontaining at least 4 carbon atoms. Typical are the reactions ofsuccinic, glutaric, adipic, pimelic, suberic or azelaic acid withsec-amyl alcohol, 3-ethyl butanol, 2-ethy1 hexanol or the branched chainsecondary alcohols undecanol or tetradecanol.

The preferred diester lubricant fluids have molecular weights rangingfrom about 300 to about 600 and freezing and pour points from about 40to less than about 'l00 F. Their flash and fire points range from about300 F. to about 500 F. and their spontaneous ignition temperatures rangefrom about 100 to about 800 F. The diesters made by reacting adicarboxylic acid with a branched chain alcohol have been found to havesuperior viscometric properties as compared with diesters made byreacting dihydric alcohols with mono-carboxylic acids and thus, diestersprepared by the former method are preferred in formulating the lubricantcompositions of this invention.

1 The diester oils may be formed by the reaction of a polycarboxylicacid with a mono-hydric alcohol, the reaction of a polyhydric alcoholwith a mono-carboxylic acid, reaction between a polyhydric alcohol witha polycarboxylic acid, or combinations of the above reactions; forexample, reaction of a polycarboxylic acid with a glycol andamono-hydric alcohol, reaction of a glycol with a polycarboxylic acid anda mono-carboxylic acid, or the reaction of a glycol, a mono-hydricalcohol, a polycarboxylic acid and a mono-carboxylic acid. The acidsmay. be mono-carboxylic aliphatic acids such as propionic acid, valericacid, 2-ethyl enanthic acid, 2,2- dipropyl butyric acid or3-(2-methylhexyl) valeric acid. They may contain unsaturated linkages asin senecioic acid, sorbic acid, or angelic acid; they may bepolycarboxylic aliphatic acids such as succinic acid, glutaric acid,azelaic acid, 5-octene-l,S-dicarboxylic acid, or 3-hexane-2,3,4-tricarboxylic acid, and they may be aromatic or cycloaliphaticacids, such as cyclohexane acetic acid, 1,4- cyclopenthylenebis aceticacid, phthalic acid, hemirnellitic acid, and terephthalic acid.

The alcohols used in preparing the polyester lubricant base materialsmay be aliphatic mono-hydric alcohols such as propanol,2-ethyl-3-hexanol, 2-ethyl-4-propyl heptanol, 2-butenol, or Z-methylpropanol. They may be polyhydric aliphatic alcohols, such as1,6-hexamethylene glycol, 1,10-decamethylene glycol, 2-heXene-l,6-diol,and 1,6-heptylene glycol; and they may be mono or polyhydric alicyclicor aromatic alcohols, such as 4-[n-(2- hydroxyethyl)phenyl]butanol,3-(2-hydroxyethyl) cycl0-,

hexanebutanol, p-(hydroxymethyl) phenethyl alcohol, 0:-methyl-p-Xylene-a,oU-diol, l,4-cyclohexane-a,o'-diethyldimethanol,2,3-bis-(4 hydroxybutyl)benzyl alcohol, 4,4'[3- (3-hydroxyhexyl)-o-phenylene] dibutanol, and 5-[3-( 3-hydroxypropyl)cyclopenta-2,4-dienylene]-3-ethyl amyl alcohol.

Thus the compounds of this invention very effectively enhance theoxidation resistance of such diester oils as diethyl oxalate;di-sec-butyl malonate; di-(Z-hexyl) succinate; di-(isoheptyl) pimelate;di-(3-decyl)suberate; disec-amyl glutarate; di-(isobutyl) glutarate;di-(Z-ethylbutyl) glutarate; di-(Z-ethylhexyl) glutarate; di-sec-amyladipate; di-(3-rnethylbutyl) adipate; diethyl adipate; di- 2-etl1ylhexyladipate; di-sec-amyl azelate; di-(isobutyl) azelate;di-(Z-ethylhexyl)azelate; di-sec-amyl sebacate; disec-butyl sebacate;di-(Z-ethylhexyl) sebacate; the glutarates, adipates, azelates andsebacates of branched chain secondary alcohols, such as undecanol,tetradecanol, etc., and in general diesters of the type described in theliterature and above as useful for synthetic lubricant purposes.

Another class of synthetic lubricants which achieve enhanced oxidativestability by the practice of this invention includes the .fsiliconelubricant. The term silicone as used herein is defined as a syntheticcompound containing silicon and organic groups. In naming specificcompounds, the nomenclature system recommended by the American ChemicalSociety Committee on Nomenclature, Spelling, and Pronunciation (Chem.Eng. News 24, 1233 (1946)) will be used. Thus, the compounds which havethe -SiOSi-linkages are the siloxanes. Derivatives of silane, SiH inwhich one or more of the hydrogens in silane are replaced with organicgroups are termed the silanes. Silicates and silicate ester compoundsare named as my derivatives of silicane and are called alkoxy or aryloxysilianes.

The silicone oils and greases serving as the base medium for thelubricant compositions of the invention include the polysiloxane oilsand greases of the type, polyalkyl-, po1yaryl-, polyalkoxy-, andpolyaryloxy-, such as polydimethyl 'siloxane, polymethylphenyl siloxane,and polymethoxyphenoxy siloxane. Further included are silicate esteroils, such as tetraalkyloxy and tetraaryloxy silanes of thetetra-Z-ethylhexyl and tetra-p-tert-butylphenyl types, and the silanes.Also included are the halogen-substituted siloxanes such as thechlorophenylpolysiloxanes. The polyalkyl, polyaryl, and polyalkylpolyaryl siloxanes are the preferred types of base medium for thesilicon containing lubricant compositions of the invention because oftheir high oxidative stability over a wide temperature range. Thepolyalkyl siloxanes, such as the dimethyl polysiloxane, are slightlypreferred over the polyaryl and polyalkyl polyaryl siloxanes becausethey show the least change in viscosity over a wide temperature range.

Certain halogen containing organic compounds have physical propertieswhich render them particularly well suited as lubricants. Ordinarily,the halogen is either chlorine or fluorine. Typical of the chlorinatedorganic compounds suitable as lubricants are the chlorodiphenyls,chloronaphthalene, chlorodiphenyl oxides and chlironated paraflin waxes.

The fluorocarbon lubricants which are enhanced by this invention arelinear polymers built up of a recurring unit which is II F01 Thefluorocarbon oils and greases are very stable chemically and have highthermal stability. These desirable physical properties appear to beclosely related to the bond distances occurring in the fluorocarbonpolymeric molecule, which may also contain chlorine bonded to carbon.

Polyalkylene glycol lubricants which are benefited by the practice ofthis invention are ordinarily the reaction product of an aliphaticalcohol with an alkylene oxide. The preferred alkylene oxides areethylene oxide and propylene oxide. Depending upon the alcohol employedand the molecular weight of the compound, the polyalkylene glycollubricants may be either water insoluble or water soluble. The molecularweights of these polymers may vary from about 400 to over 3,000. Ingeneral the polyalkylene glycol lubricants are characterized by highviscosity indices, low API gravities, low pour points and they have thegeneral formula:

Where n is small integer and depends upon the alkylene oxide employedand x is a large integer from about to about 100 depending upon themolecular weight of the finished lubricant and R represents thehydrocarbon group derived from the particular aliphatic alcoholemployed.

Another important class of synthetic materials which are enhanced by thepractice of this invention are phosphate esters which are, in general,prepared by the reaction of an organic alcohol wlth phosphoric acid andhave the general formula:

R"o-iioR where R, R and R" represent either hydrogen or an organicradical and where at least one of the groups represented by R, R and R"is an organic radical. 'Typical of these materials istricresylyphosphate. The phosphate esters are in general characterizedby excellent fire resistant properties and high lubricity. However,their thermal stability is such that they are ordinarily unsuited forhigh temperature applications above about 300 F. Other examples ofphosphate esters include: Tris-(Z-chloro-l-methylethyl)phosphate;tri-n-butyl-phosphate; tris- (2-ethylhexyl)phosphate; triphenylphosphate; tris-(pchlorophenyl)phosphate; diethyl m-tolyl phosphate;pchlorophenyl dimethyl phosphate; tris-(Z-n-butoxyethyl) phosphate;dimethyl m-tolyl phosphate; di-n-propyl-m tolyl phosphate; di-n-butylphenyl phosphate; 1,3-butylene fl-chloroisopropyl phosphate; methyldi-rn-tolyl phosphate; bis-(Z-chloro-l-methylethyl) m-tolyl phosphate;dimethyl 3,5-xylyl phosphate; 4-cl1loro-m-tolyl dimethyl phosphate;2-ethyl-1-n-propyltrimethylene methyl phosphate; 4-chloro-m-tolyll-methyltrimethylene phosphate; dimethyl noctyl phosphate, and the like.

The mineral lubricating oils which are greatly benefited by the practiceof this invention are those derived from naturally occurring petroleumcrude by distillation and various other refining processes well known inthe art. These oils include lubricating and industrial oils such ascrankcase lubricating oils, transformer oils, turbine oils, transmissionfluids, cutting oils, gear oils, industrial oils, mineral white oils,glass annealing oils, oils thickened with soaps and inorganic thickeningagents (greases) and in general, engine and industrial oils which arederived from crude petroleum and are normally susceptible todeterioration in the presence of air, particularly at elevatedtemperatures and most particularly in the presence of metal containingcatalysts such as iron, iron oxide, copper and silver.

The greases used in formulating lubricant compositions of the inventionare formed by admixing a soap with an oil of any of the types describedabove. Such soaps are derived from animal or vegetable fats or fattyacids, wool grease; rosin, or petroleum acids. Typical examples are leadoleate, lithium stearate, aluminum tristearate, calcium glycerides,sodium oleate and the like. In addition, the polyester greases maycontain unreacted fat, fatty acids and alkali; unsaponifiable matterincluding glycerol and fatty alcohols; rosin or wool grease; water; andcertain additives which may function as modifiers or peptizers.

In formulating the grease compositions of this invention, greasesprepared by admixing a lithium soap with the polyester oils arepreferred as they have superior oxidative stability as compared withgreases formulated with other soaps, such as the sodium, calcium or leadsoaps.

In preparing the improved lubricant compositions of this invention, anappropriate quantity of 2,2'-methylene bis-(4-halo-6-tert-butylphenol)is blended with the lubricant to be stabilized. If desired, preformedconcentrated solutions of the stabilizer in the base lubricant can beprepared and then subsequently diluted with additional lubricant to thedesired concentration. An advantage of this invention is the fact that2,2'-methylenebis(4-halo-6- tert-butylphenol) is easily rapidly blendedwith the base oil and because of the relative low melting point of thestabilizer, there is no danger of separation of the stabilizer from thelubricant under normal use conditions. An additional advantage of thisinvention is that 2,2- methylenebis-(4-halo-6-tert-butylphenol) ishighly compatible with the usual additives that are frequently used tofortify lubricant compositions such as detergent-dispersants, viscosityindex improvers, dyes, anti-rust additives, anti-foaming agents, and thelike.

The following examples illustrate various specific embodiments of thisinvention. The physical characteristics of the illustrative hydrocarbonoils used in the examples are shown in Table I.

TABLE I Properties of Representative Petroleum Hydrocarbon Oils Oil A BC D E F Gravity at 60 API 30. 3 30. 5 28.8 31.1 20. 5 31. 0 Viscosity,Saybolt:

Seconds at F 178.8 373. s 309. s 169. 0 249. 4 335. 4

Seconds at 210 52. 0 5s. 4. 63. s 51. 5 45. 7 68. 4 Viscosity Index.141. 9 157. 8 35. s 144. 4 Pour Point 20 -15 0 Flash Point 355 385Sulfur, Percen 0.2 0.3 0.3 0 3 0.3 0.1

EXAMPLE 1 To 100,000 parts of Oil A is added with stirring 12 parts(0.012 percent) of 2,2'-methylenebis-(4-chloro-6- tert-butylphenol). Theresulting oil is found to possess improved resistance to oxidativedeterioration.

EXAMPLE 4 To 100,000 parts of Oil D is added 100 parts (0.1 percent) of2,2-methylenebis-(4-bromo-6-tert-butylphenol). The resulting oil isfound to posses enhanced resistance against oxidative deterioration.

EXAMPLE 5 With 100,000 parts of Oil E is blended 5 parts (0.005 percent)of 2,2 methylenebis (4 chloro-6-tert-butylphenol). After mixing theresulting oil possesses enhanced resistance to oxidation.

EXAMPLE 6 To 100,000 parts of Oil F is added 150 parts (0.15 percent) of2,2'-methylenebis-(4-br0mo-6-tert-butylphenol). The resulting oilpossesses enhanced resistance against oxidative deterioration.

EXAMPLE 7 With 100,000 parts of di-(sec-amyl) sebacate having aviscosity at 210 F. of 33.8 Saybolt Universal Seconds (SUS), a viscosityindex of 133 and a molecular weight of 342.5 is blended 100 parts (0.1percent) of 2,2'-methylenebis-(4-chloro-6-tert-butylphenol) Theresulting diester lubricant possesses greatly enhanced resistanceagainst oxidative deterioration.

EXAMPLE 8 To 100,000 parts of di-(Z-ethylhexyl) sebacate having aviscosity at 210 F. of 37.3 SUS, a viscosity index of 152 and amolecular weight of 426.7 is added 1 part (0.001 percent) of2,2'-methylenebis-(4-iodo-6-tert-butylphenol). After mixing, theresultant diester lubricant possesses greatly enhanced oxidationresistance.

EXAMPLE 9 To 100,000 parts of di-(Z-ethylhexyl) adipate having aviscosity at 210 F. of 34.2 SUS, a viscosity index of 121 and amolecular weight of 370.6 is added 5,000 parts (5 percent) of2,2-methylenebis-(4-chloro-6-tert-butylphenol). After mixing, theresultant diester lubricant possesses outstanding resistance againstoxidative deterioration.

EXAMPLE 10 7 Five parts of2,2'-methylenebis-(4-chloro-6-tert-butylphenol) are blended with 2,495parts of diisooctyl azelate having a kinematic viscosity of 3.34centistokes at 65 F. (ASTM 445-52T), an ASTM slope from 40 F. 210 F. of0.693 (ASTM D341-43) and a pour point of 85 F. (ASTM D97-47). Its flashpoint is 425 F. (ASTM D9252), and its specific gravity is 0.9123 at 25C. The resulting lubricant is extremely stable to oxidation.

EXAMPLE 11 Three parts of 2,2'-methylenebis-(4-chloro-6-tert-butylphenol) are blended and mixed with 197 parts of agrease comprising 12.5 percent of lithium stearate, 1 part of polybutene(12,000 molecular Weight), 2 percent of calcium xylyl stearate and 84.5percent of di-(2-ethylhexyl) sebacate, to prepare an improved grease ofthis invention.

EXAMPLE 12 One part of 2,2-methylenebis-(4-bromo-6-tert-butylphenol) isblended with 75 parts of diisooctyl adipate having a viscosity of 35.4SUS at 210 F., a viscosity of 57.3 SUS at 100 F., a viscosity of 3,980SUS at -40 F.

8 and a viscosity of 22,500 at -65 F. Its viscosity index is 143, itsASTM pour point is below F. and its specific gravity (60 F./60 F.) is0.926.

EXAMPLE 13 An improved stable grease of this invention is prepared byblending 8 parts of 2,2'-methylenebis-(4-chloro-6-tertbutylphenol) with920 parts of grease comprising 12 percent of lithium stearate, 1 percentof polybu-tene (12,000 molecular weight), 2 percent of calcium xylylstearate, 34.0 percent of di-(Z-ethylhexyl) sebacate and 51 percent ofdi-(2-ethylhexyl) adipate.

EXAMPLE 14 Ten parts of 2,2'-methylenebis-(4-chloro-6-tert-butylphenol)are mixed with 10,000 parts of a grease comprising 11 percent of lithiumstearate, 1 percent of polybutene (12,000 molecular weight), 1 percentof sorbitan monooleate, 86.6 percent of di-[1-(2-methylpropyl)-4-ethyloctyl] seb acate.

EXAMPLE 15 Two parts of 2,2'-methylenebis-(4-iodo-6-tert-butylphenol)are blended with parts of a polymethylpolyphenyl siloxane grease ofmedium weight consistency hav ing a penetration of 240-280 (ASTM21748),a minimum melting point of 400 F. and a serviceable temperature range offrom 30 to 400 F.

EXAMPLE 16 To a siloxane fluid having a viscosity of 71 centistokes at25 C. and 24 centistokes at 75 C., a specific gravity of 1.03 at 25 C.,a freezing point of 70 C. and a flash point of 540 R, which is composedof a halogen substituted polyphenylpolyrnethyl siloxane is addedsufficient 2,2'-methylenebis-(4-chloro-6-tert-butylphenol) to give acomposition containing 1.5 percent of the additive. This oil has anextremely high degree of resistance against oxidative deterioration dueto the presence of the 2,2- methylenebis- (4-chloro-6-tert-butylphenol)EXAMPLE 17 To a phenylmethyl polysiloxane fluid having a viscosity of100-150 centistokes at 25 C., an open cup flash point of 575 F. (ASTMD-9233), a freezing point of -60 F., and a specific gravity of 1.07 at77 F. is added sufficient 2,2-methylenebis-(4-chloro-6-tert-butylphenol)to give a composition containing 0.1 percent of the additive.

EXAMPLE 18 Ten parts of 2,2'-methylenebis-(4-bromo-6-tert-buty1- phenol)are blended with about 1,000 parts of monoethyl diethoxy monoacetoxysilane (boiling point 191.5 C.) to prepare an enhanced oil of thisinvention.

EXAMPLE 19 A one percent solution of 2,2'-methylenebis-(4-chloro-6-tert-butylphenol) in tribenzyl-n-hexadecyl silane (boiling point245248 C.) constitutes an improved lubricant Within the scope of thisinvention.

EXAMPLE 20 To a poly(trifluorochloroethylene) having the formula (CFCFCI) and an average molecular weight of 880', pour point of 5 C. and aviscosity of 45 centistokes at 160 F. is added 1.25 percent of2,2-methylenebis-(4- iodo-6-tert-butylphenol) to prepare an improvedlubricant of this invention.

EXAMPLE 21 A composition consisting of 0.01 percent of 2,2-methylenebis-(4-chloro-6-tert-butylphenol) is prepared by blending anappropriate quantity of the compound With a fluorocarbon grease having apenetration of 267 millimeters at 77 F., 285 millimeters at 100 F. and300 millimeters at F. (ASTM 217-48); and a dropping point of at least400 F. (ASTM D-566-42).

EXAMPLE 22 To a polyalkylene glycol oil lubricant having a viscosity 9index of 148, ASTM pour point of 55 F., a flash point of 300 F., aspecific gravity of 0.979 and a Saybolt viscosity of 135 at 100 F. isadded 1 percent of 2,2-methylenebis-(4-chloro-6-tert-butylphenol) toprepare an extremely oxidative resistant polyalkylene glycol lubricant.

EXAMPLE 23 A composition containing 0.2 percent of2,2'-methylenebis-(4-bromo-6-tert-butylphenol) is prepared by adding anappropriate quantity of the compound to a polyalkylene glycol lubricantwhich is insoluble in water and which has a Saybolt viscosity of 62.7 at200 F., a viscosity index of 146, ASTM pour point of 40 F., a fire pointof 490 F. and a specific gravity of 0.991.

EXAMPLE 24 An improved lubricant of this invention comprising achlorinated organic compound is prepared by admixing 0.5 percent of2,2-methylenebis-(4-chloro-6-tert-butylphenol) with a chlorodiphenyl oilhaving a distiliation range of from 554 to 617 F., a Saybolt viscosityat 100 F. of about 49, a pour point of 30 F. and a specific gravity ofabout 1.267.

EXAMPLE 25 An improved hydraulic fluid and lubricant according to thisinvention is prepared by adding 2 percent of 2,2-methylenebis-(4-chloro-6-tert-butylphenol) to tricresyl phosphate.

EXAMPLE 26 To illustrate the advantages achieved by the practice of thisinvention, particularly when the compositions are subjected to elevatedtemperature, runs were conducted using the Panel Coker Test. This testmeasures the oxidative stability of oils which are maintained atelevated temperatures in the presence of air, the oils periodicallycoming in contact with a hot metal surface. This test is described inthe Aeronautical Standards of the Departments of Navy and Air Force,Spec. MIL-L-7808C, dated November 2, 1955. In these experiments, the diester lubricant was a commercially available di-(2-ethylhexyl) sebacatewhich was devoid of additives. The test was modified so that the PanelCoker apparatus was operated at 600 F. for 10 hours on a cyclingschedule the splasher being in operation for seconds followed by aquiescent period of 55 seconds. On completion of these tests the extentby which the various test oils were decomposed under these hightemperature oxidizing conditions was determined by weighing the amountof deposits which formed on the metallic panel. Under these testconditions, the use of the additive free di-(Z-ethylhexyl) sebacatecaused the formation of 138 milligrams of deposits on the metallicpanel. However, the presence of only 0.5 percent by weight of2,2'-methyleneois-(4-chloro-6- tert-butylphenol) caused a substantialreduction in panel deposit.

EXAMPLE 27 To further demonstrate the benefits resulting from thepractice of this invention, additional Panel Coker tests were carriedout using petroleum hydrocarbon lubricating oil. The test conditionswere identical with those above except that the temperature of thelubricants was maintained at 550 F. The base oil used was an initiallyadditive-free solvent-refined commercial neutral mineral lubricating oilhaving a viscosity at 100 F. of 200 SUS and a viscosity index of 95. Itwas found that the additive free oil formed 434 milligrams of deposit onthe panel when subjected to the foregoing test conditions. However, whenthe oil had been treated with one percent by weight of2,2'-methylenebis-(4-chloro-6-tert-butylphen01), there were only 82milligrams of deposit on the panel.

EXAMPLE 28 To further illustrate the effectiveness of the2,2'-methylenebis-(4-halo-6-tert-butylphenol) compounds as lubricantadditives, tests were conducted on a highly refined 10 material derivedoil having a viscosity index of 106.5 and a viscosity of 87.1 SUS at F.The oil was charged in separate samples (with and without an additive ofthis invention) to an apparatus for measuring the oxidative stability ofthe oil. The apparatus consists of a glass vessel having a 12 millilitercapacity and an inlet tube which can be connected to a mercurymanometer. After the oil is charged, the vessel is flushed with oxygenat atmospheric pressure and then connected to the mercury manometer. Thevessel is then immersed in a constant temperature bath at 150 C.whereupon changes in the oxygen pressure are indicated on the manometer.The manometer is observed until a rapid pressure drop in the vesseloccurs. The time from immersion to the initiation of the pressure dropis the induction period of the oil. To all samples, ferric hexoate isadded to catalyze oxidation and make the test more severe. Theconcentration of the iron salt is adjusted to 0.05 percent based on Fe OOne milliliter of the oil is charged to the apparatus in each test. Intests of this nature the base oil has an induction period of from 2 to 3minutes, showing that it is completely unstable to oxidativedeterioration at 150 C. However, when the oil contained 1.0x 10'- molesper liter of 2,2'-methylenebis-(4- chloro-6-tert-butylphenol),theinduction time was 349 minutes. Thus the stability of the oil was raisedby the enormous factor of about -175 times its original value.

EXAMPLE 29 Another illustration of the improvements in oil sta bilityachieved by the practice of this invention are shown by PolyveriformOxidation Stability Tests, described in the paper entitled FactorsCausing Lubricating Oil Deterioration in Engines (Industrial andEngineering Chemistry, Analytical Edition, 17, 302, (1945)). See also ABearing Corrosion Test for Lubricating Oils and Its Correlation withEngine Performance (Analytical Chemistry, 21, 737, (1949)). This testeffectively evalutes the performance of lubricating oil antioxidants.The test equipment and procedure employed and correlations of theresults with engine performance are discussed in the first paper abovementioned.

The amount of oxidation taking place during the test is measured interms of acid number and viscosity increase of the oil. By contrasting acomposition of this invention with a similar oil not containing anadditive of this invention, the outstanding benefits are illustrated.For example, in a set of tests conducted as described in the firstreference cited above, modified to the extent that the steel and coppertest piece described in the publication were omitted, a non-additivelubricating oil was compared With the same oil containing 1.0 weightpercent of the preferred compound of this invention, 2,2-methylenebis-(4-chloro-6-tert-butylphenol). In order to make the test assevere as possible 70 liters of air per hour were passed through the oilfor a period of 20 hours while the oil temperature was maintained at 300F. The non-additive oil had an acid number of 6.0 after completion ofthe test and its viscosity had increased by 103 percent. In distinctionto this the sample of oil containing 1.0 weight percent of2,2-methylenebis-(4-chloro- 6-tert-butylphenol) had an acid number ofonly 1.6 and had suffered only a 23 percent increase in viscosity duringthe test. In addition to this, essentially no sludge had formed in theoil of this invention.

EXAMPLE 30 To still further illustrate the benefits derived from thisinvention tests were conducted on an electromotive diesel oil having aviscosity index of 54 and a viscosity of 919 Saybolt Universal Secondsat 100 F. In this test the oil is heated at 325 F. with agitation forhours. Two metal catalysts are employed to promote degradation of theoil, namely, a silver plated wrist pin bushing specimen and a coppermetal catalyst specimen. Degradation of the oil is determined by acidnumber after the test and percent viscosity increase at 100 F. Inaddition the condition of the silver specimen indicates poor performancein the oil. One sample of the oil employed in this test contained acommercially available zinc dithiosulfate in amount equivalent to 0.02weight percent phosphorus. In this test the acid number of the oilincreased to 2.6 and there was a 47 percent increase in the viscosity.However, when an oil containing 4 percent of a barium sulfonate and 0.05percent by Weight of 2,2 methylenebis (4 chloro 6 tert butylphenol) wassubjected to the test, the final acid number was only 0.5 and theviscosity had increased only 31 percent. In addition the silver testspecimen came through the test essentially unchanged. In the lubricantcompositions of this invention effective use can be made of otheradditives which are known to the art, such as other inhibitors,detergent-dispersants, pour point depressants, viscosity indeximprovers, antifoam agents, rust inhibitors, oiliness or film strengthagents, dyes and the like. Of the inhibitors which can be effectivelyused in combination with the additives of this invention are sulfurizedsperm oil, sulfurized terpenes, sulfurized paraifin wax olefins,aromatic sulfides, alkyl phenol sulfides, lecithin, neutralizeddithiophosphates, phosphorus penta-sulfide-terpene reaction products,diphenylamine, phenylnaphthyl amine, fi-naphthol, pyrogal- 101, and thelike. Typical of the detergent additives that can be used in thecompositions of this invention are metallic soaps of high molecularweight acids, such as aluminum naphthenates, calcium phenyl stearates,calcium alkyl salicylates, alkaline earth metal petroleum sulfonates,alkaline earth metal alkyl phenol sulfides (barium amyl phenol sulfide,calcium octyl phenol disulfide, etc.), metal salts of wax-substitutedphenol derivatives and the like. Of the viscosity index improvers andpour point depressants, effective use can be made of polymers of theesters of methacrylic acids and higher fatty alcohols and thecorresponding polymers of esters of acrylic acid and higher fattyalcohols. These and other additives which can be employed in thecompositions of this inventions will now be Well known to those skilledin the art.

The compounds of this invention are particularly effective antioxidantsfor use in steam turbine oils. This is demonstrated by making use of thestandard test procedure of the American Society for Testing Materialsbearing ASTM designation D94354. According to this test procedure, 300ml. of a suitable test oil is placed in contact with 60 ml. of water andthe resulting oil-water system is maintained at a temperature of 95 C.while passing oxygen therethrough at a rate of three liters per hour.Oxidation is catalyzed by the use of iron and copper wire. Periodicallymeasurements are made of the acid number of the test oil and failure ofan antioxidant is indicated by an acid number in excess of 2.0. It isfound that when the various compositions of this invention are added insmall antioxidant quantities to steam turbine oils, substantialresistance against oxidative deterioration results.

The compounds of this invention are very effective antioxidants forgrease. The potency of the compounds of this invention in this respectis demonstrated by conducting the Norma Hoffman Grease OxidationStability Test, ASTM Test Procedure D94250. It is found that thepresence of minor proportions of the compounds of this invention inconventional greases greatly inhibits oxidative deterioration. By way ofexample an initially antioxidant-free lithium base grease is modified tothe extent that it contains 0.5 percent by weight of the product ofExample 13, and is subjected to the above oxidation stability test. Itis found that the presence of the composition produced by the process ofthis invention greatly retards oxygen absorption by the grease.

1 The stabilizers of this invention are also excellent additives totetraalkyllead antiknock compositions. The tetraalkyllead antiknockagents which are stabilized according to this invention are representedby such compounds as tetramethyllead, tetraethyllead, tetrapropyllead,

dimethyldiethyllead, trimethylethyllead, and the like, or mixturesthereof. Such compounds containing from 4 to about 12 carbon atoms, oneatom of lead and a pluralityof lead-to-carbon bonds, are capable ofincreasing the octane quality of gasoline when employed therein inantiknock quantities0.5 to 6.5 grams of lead per gallon.Halogen-containing compounds such as triethyllead bromide may also bestabilized according to this invention.

The scavengers which are preferably, but not necessarily, present in theantiknock compositions of this invention are organic halide compoundswhich react with the lead during combustion in the engine to formvolatile lead halide. The halogen of these scavengers has an atomicweight between 35 and that is, the active scavenging ingredient ischlorine and/ or bromine. Such scavengers include carbon tetrachloride,propylene dibromide, 2-chloro-2,3 dibromobutane, 1,2,3 tribromopropane,hexachloropropylene, mixed bromoxylenes, 1,4-dibromobutane,1,4-dichloropentane, ,B,,8'-dibromodiisopropyl ether,fi,,B-dichlorodiethyl ether, trichlorobenzene, dibromotoluenes, and ingeneral those disclosed in US. Patents 1,592,954; 1,668,022; 2,364,921;2,479,900; 2,479,901; 2,479,902; 2,479,903; and 2,496,983. In short, weprefer to employ scavengers containing only elements selected from thegroup consisting of carbon, hydrogen, bromine, chlorine and oxygen. Theamount of scavenger used is from about 0.5 to about 2.0 theories, atheory being defined as the quantity required to react with the lead toform lead halidei.e., 2 atoms of halogen per atom of lead. When we usemixtures of bromine-containing and chlorine-containing scavengers,particularly bromo and chlorohydrocarbons, we can employ concentrationsand proportions as described in US. Patent 2,398,281. Suchconcentrations are sufficient to control the amount of deposits formedin the engine.

The tetraalkyllead antiknock compositions of this invention may containother ingredients such as dyes for identification purposes, metaldeactivators, diluents and the like.

Antiknock compositions containing tetraalkyllead antiknock agents areemployed by adding them to gasoline to improve the antiknock qualitythereof. Such gasolines both before and after addition of the antiknockfluid are benefited by the practice of this invention. Thus gasolines towhich have been added a compound of this invention are found to be morestable upon prolonged periods of storage.

The following examples illustrate gasoline embodiments of thisinvention.

EXAMPLE 31 To 10,000 parts of a grade 115/145 aviation gasolinecontaining 4.5 ml. of tetraethyllead per gallon which has an initialboiling point of F. and a final boiling point of 330 F. and an APIgravity of 71.0 is added 0.5 percent of2,2'-methylene-bis-(4-chloro-6-tert-butylphenol).

EXAMPLE 32 To a gasoline containing 26.6 percent aromatics, 20.8 percentolefins and 52.6 percent saturates and which has an API gravity of 62.1is added 0.1 percent of 2,2- methylene-bis- (4-bromo-6-tert-butylphenolSimilarly, the compounds of this invention may be added with benefit togasoline of Whatever nature and however processed.

As noted above the compounds of this invention are also extremely usefulin inhibiting and stabilizing nonpetroleum fats and oils normallysubject to the deteriorating effect of oxidative rancidity. Inparticular, compounds of this invention are excellent stabilizers foranimal fats and oils, especially lard, against the effects of rancidity.The compounds of this invention may be used in concentrations from 0.001to about 0.1 weight percent in this embodiment of the invention. Inaddition, an acid synergist may be employed to promote the activity ofthe additives of this invention. These synergists which mutuallycooperate with the compounds of this invention, particularly2,2-methylene-bis-(4-chloro- 6-tert-butylphenol), to produce adisproportionately large increase in effectiveness in stabilizing fattymaterials including citric acid, phosphoric acid, ascorbic acid, ethylacid phosphate, glucuronolactone, phytic acid, tartaric acid andaconitric acid.

In formulating the stabilized non-petroleum fats and oils of thisinvention, the additive or combination of additives is incorporated byappropriate means into the substrate to be stabilized.

Hydrocarbon polymers which are stabilized against oxidativedeterioration according to this invention include natural rubber, GRSand GRN rubbers, butyl rubber, methyl rubber, polybutene rubber,butadiene rubbers, piperylene rubbers, dimethylbutadiene rubbers,polystyrene, polybutadiene, polyisobutylene, polyethylene,isobutylene-styrene copolymer and, in general, elastorneric hydrocarbonpolymers which are normally susceptible to oxidative deterioration. Suchpolymers are well known in the art and besides being susceptible ofoxidative deterioration are characterized by having molecular weightsabove about 10,000. The problem resulting from heat, light and catalystpromoted oxidative deterioration in such hydrocarbon polymers isintensified because of free radical formation within the polymers. Thisleads to various forms of physical and chemical degradation such aschain scission, autocatalytic oxidation, reduction in molecular weightand loss of original physical properties. The net result is that thedesirable, useful and necessary properties of the polymers which areassociated with their original chemical structure and molecular weightsare lost to a greater or lesser extent unless the polymers arestabilized against such deterioration.

EXAMPLE 33 To a synthetic rubber master batch comprising 100 parts ofGR% rubber having an average molecular weight of 60,000, 5 parts ofmixed zinc propionatestearate, 50 parts of carbon black, 5 parts of roadtar, 2 parts of sulfur and 1.5 parts of mercaptobenzothioazole isincorporated 1.5 parts of 2,2'-methylenebis-(4-chloro-6-tert-butylphenol). This batch is then cured for 60 minutes at 45pounds per square inch of steam pressure.

EXAMPLE 34 One percent of 2,2-methylenebis(4-chloro-6-tert-butylphenol)is added to a synthetic rubber master batch comprising 100 parts of GR-Srubber having an average molecular weight of 100,000, 5 parts of zincstearate, 50 parts of carbon black, 5 parts of road tar, 2 parts ofsulfur and 1.5 parts of mercaptobenzothiazole. This batch is then curedas described in Example 33.

EXAMPLE 35 Two parts of 2,2'-methylenebis-(4-bromo-6-tert-butylphenol)is incorporated in 100 parts of a raw butyl rubber prepared by thecopolymerization of 90 percent of isobutylene and 10 percent of isopreneand having an average molecular weight of 100,000.

EXAMPLE 36 14 on the weight of the batch of 2,-2-methylenebis-(4-chloro-6-tert-butylphenol) EXAMPLE 38 A dry blend of polystyrene and2,2-methylenebis-(4- chloro-6-tert-butylphenol) is prepared by mixing 1part of this phenol with parts of polystyrene having an averagemolecular weight of 50,000.

EXAMPLE 39 0.25 percent by weight of 2,2-methylenebis-(4-chloro-6-tert-butylphenol) is incorporated in polybutadiene having an averagemolecular weight of 50,000.

EXAMPLE 40 To natural rubber (I-Ievea) is added 0.02 percent of2,2-methylenebis-(4-iodo-6-tert-butylphenol) The above examplesillustrate the improved compositions of this invention. Other suchcompositions and the methods of preparing the same will now be apparentto the person skilled in the art.

EXAMPLE 41 To illustrate the enhanced oxygen resistance of thehydrocarbon polymer compositions of this invention, a natural rubbercompounded into a typical tire-tread formula is selected for test. Onerequisite of such stocks is that the desirable properties incorporatedtherein by careful selection of the compounding ingredients and curetime shall be maintained during extended periods of storage and use inthe presence of oxygen. Comparison of various rubber stocks is bestcarried out on stocks initially having the same state of cure. The mostreliable means for determining the state of cure is by the T-50 test,ASTM designation: D-599-40T, described in the ASTM Standards for 1952,Part 6. This test measures the temperature at which a test piecerecovers its elasticity when it is stretched at room temperature, frozenat a sufficiently low temperature to cause it to lose its elasticproperties, and then gradually warmed. In practice the temperature notedis that at which the sample recovers to 50 percent of the originalelongation and is, therefore, referred to as the T-50 value. Stocks fortesting and comparison are cured for a time sufiicient to have a T50value of 4.5 C. so that a valid comparison of the properties can bemade. The accelerated aging is conducted by the procedure of ASTMdesignation: D57252, described in the ASTM Standards for 1952, Part 6,for a period of 96 hours at a temperature of 70 C., with an initialoxygen pressure in the test bomb of 300 pounds per square inch gauge onspecimens having the following composition:

To demonstrate the protection afforded to the rubber by the inhibitorsof this invention, the tensile strength and the ultimate elongation ofstocks prepared by the addition of an inhibitor of our invention aredetermined before and after aging. These properties are compared withthe same properties determined on an identical rubber stock notprotected by an inhibitor. Both of these properties are determined bymeans of the test procedure of ASTM designation: D412-5 1T, fullydescribed in ASTM Standards for 2, Part 6. The tensile strength is thetension load per unit cross-sectional area required to break a testspecimen, while the ultimate elongation is the elongation at the momentof rupture of a test specimen. A decrease in the values for either ofthese properties upon aging represents a decrease in the usefulness ofthe article fabricated therefrom, so that the degree to which theseproperties are retained is a direct measure of the utility of theprotective substance.

The novel 2,2'-methylenebis-(4-halo-6-tert-butylphenol) compounds ofthis invention are prepared by a process which comprises reacting a4-halo-6-alkylphenol having the formula:

where X is a halogen such as chlorine, bromine and iodine withformaldehyde in the presence of an alkali metal hydroxide and anon-aqueous solvent. This reaction is illustrated by the followingexamples:

EXALIPLE 42 In a reaction vessel equipped with reflux condenser, heatingmeans, means for agitating reactants and means for charging liquidreactants was placed 3142 parts of isopropanol and 66 parts of potassiumhydroxide. The mixture was agitated until the potassium hydroxide wascompletely dissolved at which point 1846 parts of4-chloro-6-tert-butylphenol was added and the mixture was heated to 45C. While maintaining the temperature, 420 parts of a 36.3 percentformalin solution was added incrementally. The reaction temperature wasthereafter maintained with agitation for 6 hours, cooled to roomtemperature and acidified with about 200 parts of dilute hydrochloricacid. The acidified mixture was added to about 5500 parts of petroleumether, the isoproanol was extracted with water and the Water phasediscarded. The organic phase was then distilled through a helix packedcolumn and 665 parts of 2,2-methylenebis-(4-chloro-6- tert-butylphenol)were recovered at 209213 C. at 0.3 ml. pressure. A portion of thismaterial was recrystallized from petroleum ether to yield white crystalsof pure 2,2'-methylenebis-(4-chloro-6-tert-butylphenol) having a meltingpoint of 1141l4.5 C. Upon analysis these crystals were found to contain64 percent carbon, 6.6 percent hydrogen and 19.6 percent chlorine. Thecalculated content for the compound is 66.1 percent carbon, 6.8 percenthydrogen and 18.6 percent chlorine. An infrared spectrum of the compoundshowed bands of a partially hindered hydroxyl of a bisphenol compound.The ring substitution as determined from the infrared spectrum showedthe compound to contain a 1,2,4,6-substituted benzene ring.

EXAMPLE 43 Using isopropanol as a solvent 2-tert-butyl-4-chlorophenolwas reacted with 37 percent aqueous formaldehyde in the presence ofpotassium hydroxide as a catalyst for 17 hours at reflux temperature.The following procedure was used: 19 parts of the potassium hydroxidecontained in about 100 parts of isopropanol was added to the reactionvessel which was then flushed with nitrogen, 61 parts of 2-tert-butyl-4-chlorophenol and about 7 parts of formaldehyde as a 37percent aqueous solution were simultaneously added. After the additionof the formaldehyde the reaction mixture was refluxed. After thereactionthe mixture was taken up in n-hexane, washed well with water,dried and stripped under reduced pressure to remove the isopropanolsolvent. The product of this work-up procedure was a viscous oil whichwas fractionally distilled to yield 26 percent of the starting phenol, 5percent of 6-tert-butyl-4-chloro-2-hydroxymethylphenol (boiling point125l27 C. at 0.5 mm. of mercury pressure) and 11 percent of2,2'-methylenebis-(4-chloro-6- tert-butylphenol), which boiled atISO-220 C. at the reduced pressure of 0.5 mm. and which had a meltingpoint of 109-110" C. The structure of the compound was confirmed byinfrared analysis.

IEXAilIPLE 4:4 1

Following the procedure of Example 42, an appropriate quantity of2-tert-butyl-4-brornophenol is reacted with formaldehyde in the presenceof sodium hydroxide and ethanol to produce2,2-rnethylenebis-(4-bromo-6-tertbutylphenol) Similarly, 2,2methylenebis ('4 iodo 6 tert butylphenol) may be prepared by employingZ-tert-butyl- 4-i0dophenol as the starting material.

In the above reaction a lower aliphatic alcohol is employed as asolvent. The preferred solvents are ethanol and isopropanol. Thereaction is conducted at temperatures varying from 20 to about C. andmay be continued for from one-half to about 40 hours, depending upon thetemperature conditions employed.

The product 2,2'-rnethylenebis-(4-halo-6-tert-butylphe- 1101) ispreferably recovered from the reaction mixture by first stripping thesolvent and then distilling the reaction residue at reduced pressures.The reduced pressure employed should be adjusted so that the desiredproduct distills at temperatures in the range of from to 250 C. andpreferably in the range of to about 220 C.

We claim:

1. A compound having the formula:

wherein X is a halogen selected from the class consisting of chlorine,bromine and iodine.

2. 2,2'-methylenebis-(4-chloro-6-tert-butylphenol).

References Cited in the file of this patent UNITED STATES PATENTS OTHERREFERENCES Beaver et al.: Jour. Amer. Chem. Soc., vol. 74 (1952), pages3410-11 (2 pages).

1. A COMPOUND HAVING THE FORMULA: 